Respirator having a mouthpiece arranged laterally of the filter

ABSTRACT

A respirator includes a housing with an annular interior wall in which is mounted a filter. An outer wall of the housing has an inlet at one side and a flow space from the inlet through a converging passage defined by a cover on one end of the filter and then through a diverging passage after flow through the filter. The diverging passage communicates at the opposite side of the filter with a mouthpiece which is advantageously covered by removable enclosure when not in use.

United States Patent [1 1 Wachter Nov. 20, 1973 1 RESPIRATOR HAVING AMOUTHPIECE ARRANGED LATERALLY OF THE FILTER [75] Inventor: Karl-AugustWachter, Lubeck,

Germany [73] Assignee: Dragerwerk Aktiengesellschaft,

Lubeck, Germany [22] Filed: Nov. 10, 1971 [21] Appl. No.: 197,266

[30] Foreign Application Priority Data Nov. 20, 1970 Germany P 20 57093.8

[52] US. Cl. 128/147 [51] Int. Cl A621) 7/00 [58] Field of Search128/147, 146.6, 142.6,

128/201, 212, 208, 140 R, 141, 142.4, 146, 146.3; 55/512, 516, 518, 520,DIG. 35, 515

[56] References Cited UNITED STATES PATENTS 2,295,296 9/1942 Schmidt128/1466 X 2,610,624 9/1952 Haller et a]. 128/147 PrimaryExaminerRichard A. Guadet Assistant Examiner-Lee S. Cohen Attorney-JohnJ. McGlew et al.

[5 7 ABSTRACT A respirator includes a housing with an annular interiorwall in which is mounted a filter. An outer wall of the housing has aninlet at one side and a flow space from the inlet through a convergingpassage defined by a cover on one end of the filter and then through adiverging passage after flow through the filter. The diverging passagecommunicates at the opposite side of the filter with a mouthpiece whichis advantageously covered by removable enclosure when not in use.

10 Claims, 2 Drawing Figures Patented Nov. 20, 1973 3,773,043

RESPIRATOR HAVING A MOUTHPIECE ARRANGED LATERALLY OF THE FILTERBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates in general to breathing devices and, in particular, to a new anduseful respirator with an interior wall holding a filter and with airflow from an inlet on one side through the filter to its opposite endand then to a mouthpiece at the opposite side which has a bite cam forengagement by a persons mouth.

2. Description of the Prior Art Small size respirators which may becarried in a pocket of the wearer, and which contain a filter which islodged in a relatively flat housing are known. The Hat housing is filledup over its flat cross-section by a filter mass which is closed off onboth sides by a perforated metal sheet. On the gas outlet side, thehousing is closed off by a cover which extends laterally, and includes aconnection piece for a mouthpiece. Viewed in the direction of flow ofthe air through the filter material, the mouthpiece lies laterally nextto the filter material. The cover includes a central portion whichcarries the mouthpiece and the next valve is located in this location.The housing may be opened on the air inlet side so that the perforatedmetal sheet holding the filter material forms the outer boundary. It isalso known to provide a respirator construction which includes a filteroutlet side which is closed off by an arch, a cover which is provided inthe central portion with openings which are covered by a membrane whichacts as an inhalation valve (U.S. Pat. No. 2,610,624). U. S. Pat. No.2,626,678 also shows a construction in which the filter is under vacuumand is hermetically sealed on the filter inlet side by a cover. Thecover rests against a closure ring against which it is pressed by theair pressure and it is opened by a lever connected therewith.

A disadvantage of all of the known constructions is that they requirethe manufacture of many individual parts, and they are costly to make.Because of the deflection of the air which is circulated therethrough,the known respirators have a relatively high resistance on the filteroutlet side. Moreover, the flow through the filter is irregular. Inwearing such devices, the air inlet aperture is directly in front of theusers chest so that at certain head positions, the inlet aperture mayrest against the wearers suit, and this makes breathing difficult. Theknown devices have complicated closures for the inhalation aperture.

SUMMARY OF THE INVENTION In accordance with the invention, there isprovided a respirator of simple construction and low costs, which may bemanufactured very easily and assembled and stored without difficulty.The device is made as small as possible so that it can be carried in apocket of the user. The respiration flow distance of the device is lowin all positions of use. The flow through the respirator filter isuniform. For this purpose, the respirator comprises a housing with aninterior annular wall which carries a filter and which is connected atits one side to an inlet which communicates with a converging passage tothe full filter area, for flow through the filter to the opposite end.The mouthpiece positioned at the opposite side connects through apassage which diverges outwardly to the mouthpiece from the opposite endof the filter. The cover for the housing forms the coverging passage onthe inlet end of the filter and the diverging passage toward themouthpiece on the mouthpiece end. The filter is arranged so that theflow is across its major dimension and cross-section through arelatively shallow depth filter. The flow resistance of such aconstruction is low and the flow through the filter is uniform. Theinlet aperture of the filter can be hermetically closed withoutdifficulty and it is located so that the inlet aperture is not blockedin the common positions of use.

A favorable form of the invention is to arrange the air inlet apertureon the side opposite to the mouthpiece. This has the advantage that thewearer instinctively recognizes the position of the inlet apertureimmediately and this facilitates the handling of the device.

In a further embodiment of the device, the housing contains an internaladaptor flange of circularly cylindrical formation which provides amounting for the filter material, and the outer housing wall is madeovalshaped so that it extends beyond each end of the filterholdingparts. The air inlet is arranged in one end of the outer housing and themouthpiece is arranged in the opposite end, and the passage spacedefined between the air inlet and the filter ring, provides an inletflow space while the opposite side provides an outlet flow space to themouthpiece. The ring flange for holding the filter is advantageouslymade of one piece with the housing, and with the mouthpiece connectionon one side thereof. One of the cover portions on an end of the filtermay also be made integral with the housing and the other cover area maycomprise a readily connectable part. Otherwise, the two cover parts maybe made of identical configuration. They are applied over opposite endsof the filter in an opposite manner.

The mouthpiece advantageously carries a nose clamp therein which may beremoved by stretching a connecting spring in order to immediatelyposition it in a location for use.

Accordingly, it is an object of the invention to provide an improvedrespirator construction which includes a flat housing having an internalmounting ring for a filter but with an inlet on one side which connectsthrough a passage to one end of the filter, and a mouthpiece at theopposite side which connects through a connecting passage to theopposite end of the filter.

A further object of the invention is to provide an improved filterconstruction which includes a flat housing having an internal mountingring of circularly cylindrical form carrying a filter and with the outerwall thereof forming a crescent-shaped flow space at each side, one sidebeing connected to an inlet and the opposite side being connected to amouthpiece.

A further object of the invention is to provide a respirator which issimple in design, rugged in construction, and economical to manufacture.

The various features of novelty which characterize the invention arepointed out with particularity in the claims annexed to and forming apart of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its uses,reference should be had to the accompanying drawing and descriptivematter in which there is illustrated a preferred embodiment of theinvention.

BRIEF DESCRIPTION OF THE DRAWING In the Drawing:

FlG. l is a vertical sectional view of a respirator constructed inaccordance with the invention; and

FIG. 2 is a horizontal sectional view of the respirator.

GENERAL DESCRIPTION OF THE PREFERRED EMBODlMENT Referring to thedrawings in particular, the invention contained therein, comprises arespirator housing 1, which is advantageously an injection molding ofplastic or similar material, and which includes an integrally formedmouthpiece part 2 extending outwardly from one side thereof. Theinterior of the housing includes an annular cylindrical wall for afilter mounting ring 5 in the interior of which is mounted a filter 3.The filter 3 may be formed of a metal pot 4, which may beinjection-molded into the housing 1. The filter material 6 is mountedwithin the metal pot 4 and is held between two cover screens forperforated plates 7, 7'. One of the cover screens 7 may be formed in themolding process. It is also possible to produce the filter pot 4 of thefilter 3 directly in the molding process.

In accordance with a further feature of the invention, the housing 1 ismade with an exterior oval-shaped wall so as to define an air inletspace 9 at one side, and an air discharge flow space 10 at the oppositeside, both spaces being of a crescent-shaped cross-section. An air inletaperture 8 is arranged centrally to connect into the inlet space 9, andthis is diametrically opposite the mouthpiece connection piece 2, whichcommunicates with the outlet space 10.

After the filling of the filter 3 for the insertion of the filter, asthe case may be, covers 12 and 12 are arranged at respective oppositeends of the filter. The covers 12 and 12' are of identical configurationbut are oppositely positioned, and the cover 12 defines an inlet flowspace 11a, which gradually converges toward the filter 3, whereas thecover 12' defines an outlet flow space 11b which diverges outwardly intocommunication with the outlet space 10. The covers 12 and 12 may beconnected to the housing by a gas-tight connection, such as gluing orwelding. Because the air flow inlet space 11a diminishes incross-section in the flow direction, and the air flow space lib at theopposite end of the filter 3 increases in cross-section in the flowdirection, the flow considerations are favorable so that the flowthrough the filter is uniform.

The mouthpiece 2 carries a rubber mouthpiece 13 with bite cam 14. Inorder to save space in packing of the device, the mouthpiece carries aspring 15, which is engaged in the interior of the mouthpiece l3, andwhich is connected at its outer end to a nose clamp 20.

The air inlet-opening 8 is closed by a plug 1.61, and the mouthpiece 13is closed by a cap l7 when the device is not in use. Both of theseelements are connected together by a closure band l8 which encircles therespira tor. The plug 16, the cap 17 and the band l8 may form a commonmolded part so that they remain intercon' nected and do not becomedisassociated. The closure band 18 is provided with a closure for theends (not shown). So that it will not be damaged, protruberances 19 areprovided on one or both sides of the closure on the cover 12 and i2 sothat the device is protected from damage from wearing. The closures inand 17 close the device completely gas-tight and in a satisfactorymanner, and permanently, even when it is stored for a long time. Theentire form of the respirator is such that it easily slides over allobjects and forms no resistance. Sharp corners and edges are avoided.The device can be accommodated without trouble and resistance in a coator a smock pocket.

For use, the wearer merely removes the closure band l8 and takes off theclosures 16 and 17. He places the nose clamp 20 over his nose and pushesthe respirator mouthpiece into his mouth. The device is suitableprincipally as an escape filter device.

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

1. A respirator comprising a housing having a flat cylindricai filterreceiving wall defining a space therein for a filter, a filter withinsaid receiving wall space, a mouthpiece in said housing adjacent to andexterior of one end of said filter receiving wall, an air inlet definedin said housing adjacent to and exterior of the diametrically oppositeside of said filter receiving wall, and cover means overlying each sideof said space and spaced from said filter receiving wall and defining aflow space from said inlet on one end of said filter with graduallynarrowing flow space and a flow space on the opposite end of said filterwith gradually widening flow space area to said mouthpiece.

2. A respirator, according to claim 1, wherein said cover means includesa separate cover on each end of said housing, said covers being ofidentical configuration but being arranged in a reverse manner onrespective ends of said filter.

3. A respirator, according to claim 1, including a nose clamp connectedto said mouthpiece and being inscrtable therein.

4. A respirator, according to claim 1, wherein said cover means includesa protuberance thereon on each side forming a protection.

5. A respirator comprising a housing, a filter mounted in said housing,a mouthpiece in said housing adjacent one side of said filter, an airinlet defined in said housing adjacent the opposite side of said filter,and cover means on each end of said housing defining a flow space fromsaid inlet on one end of said filter with gradually converging walls anda flow space on the opposite end of said filter with gradually divergingwalls to said mouthpiece, said housing including an outer oval-shapedwall and an inner circularly cylindrical wall centered within theoval-shaped housing, said filter being disposed within the circularring-shaped wall, said inner ring-shaped wall defining a crescent-shapedflow space at each side adjacent said mouthpiece and said inletrespectively.

6. A respirator, according to claim 5, wherein said ring-shaped wall ismade integral with said housing and said mouthpiece.

7. A respirator, according to claim 5, wherein said filter includes aperforated wall at one end formed integrally with said ring-shaped wall.

8. A respirator comprising a housing, a filter mounted in said housing,a mouthpiece in said housing adjacent one side of said filter, an airinlet defined in said housing adjacent the opposite side of said filter,and cover means on each end of said housing defining a flow space fromsaid inlet on one end of said filter with gradually converging walls anda flow space on the opposite end of said filter with gradually divergingwalls to said mouthpiece, a cap extending over said mouthpiece, said airinlet aperture having a closure cap thereover, and an encircling bandconnecting said air inlet closure cap and said mouthpiece cap.

9. A respirator, comprising a housing having an ovalshaped outer walland an inner circularly cylindrical wall joined at respectivediametrically opposite sides to said outer wall and defining acrescent-shaped flow space in respect to said outer wall at each sidewhich is not connected to said outer wall, a mouthpiece formed on saidouter wall connecting into one of the crescent-shaped flow spaces, aninlet formed on theopposite outer wall connecting into the othercrescentshaped flow space, a filter mounted within said inner wall, acover arranged on each end of said filter and defining a flow space onthe inlet which flows from said crescent-shaped space over saidcylindrical wall to one end of said filter and from the opposite end ofsaid filter over said cylindrical wall to said mouthpiece.

10. A respirator, according to claim 9, wherein said flow spaces on eachend of said filter are of wedgeshaped configuration and said flow spacefrom said inlet to said filter gradually narrows toward said filter,said flow space from the opposite end of said filter to said mouthpiecegradually widens.

1. A respirator comprising a housing having a flat cylindrical filterreceiving wall defining a space therein for a filter, a filter withinsaid receiving wall space, a mouthpiece in said housing adjacent to andexterior of one end of said filter receiving wall, an air inlet definedin said housing adjacent to and exterior of the diametrically oppositeside of said filter receiving wall, and cover means overlying each sideof said space and spaced from said filter receiving wall and defining aflow space from said inlet on one end of said filter with graduallynarrowing flow space and a flow space on the opposite end of said filterwith gradually widening flow space area to said mouthpiece.
 2. Arespirator, according to claim 1, wherein said cover means includes aseparate cover on each end of said housing, said covers being ofidentical configuration but being arranged in a reverse manner onrespective ends of said filter.
 3. A respirator, according to claim 1,including a nose clamp connected to said mouthpiece and being insertabletherein.
 4. A respirator, according to claim 1, wherein said cover meansincludes a protuberance thereon on each side forming a protection.
 5. Arespirator comprising a housing, a filter mounted in said housing, amouthpiece in said housing adjacent one side of said filter, an airinlet defined in said housing adjacent the opposite side of said filter,and cover means on each end of said housing defining a flow space fromsaid inlet on one end of said filter with gradually converging walls anda flow space on the opposite end of said filter with gradually divergingwalls to said mouthpiece, said housing including an outer oval-shapedwall and an inner circularly cylindrical wall centered within theoval-shaped housing, said filter being disposed within the circularring-shaped wall, said inner ring-shaped wall defining a crescent-shapedflow space at each side adjacent said mouthpiece and said inletrespectively.
 6. A respirator, according to claim 5, wherein saidring-shaped wall is made integral with said housing and said mouthpiece.7. A respirator, according to claim 5, wherein said filter includes aperforated wall at one end formed integrally with said ring-shaped wall.8. A respirator comprising a housing, a filter mounted in said housing,a mouthpiece in said housing adjacent one side of said filter, an airinlet defined in said housing adjacent the opposite side of said filter,and cover means on each end of said housing defining a flow space fromsaid inlet on one end of said filter with gradually converging walls anda flow space on the opposite end of said filter with gradually divergingwalls to said mouthpiece, a cap extending over said mouthpiece, said airinlet aperture having a closure cap thereover, and an encircling bandconnecting said air inlet closure cap and said mouthpiece cap.
 9. Arespirator, comprising a housing having an oval-shaped outer wall and aninner circularly cylindrical wall joined at respective diametricallyopposite sides to said outer wall and defining a crescent-shaped flowspace in respect to said outer wall at each side which is not connectedto said outer wall, a mouthpiece formed on said outer wall connectinginto one of the crescent-shaped flow spaces, an inlet formed on theopposite outer wall connecting into the other crescent-shaped flowspace, a filter mounted within said inner wall, a cover arranged on eachend of said filter and defining a flow space on the inlet which flowsfrom said crescent-shaped space over said cylindrical wall to one end ofsaid filter and from the opposite end of said filter over saidcylindrical wall to said mouthpiece.
 10. A respirator, according toclaim 9, wherein said flow spaces on each end of said filter are ofwedge-shaped configuration and said flow space from said inlet to saidfilter gradually narrows toward said filter, said flow space from theoppoSite end of said filter to said mouthpiece gradually widens.